Synthesis, Characterization and Adsorption Property of Expanded Graphite/Conducting Polymer Composite

2011 ◽  
Vol 322 ◽  
pp. 93-97 ◽  
Author(s):  
Min Cong Zhu ◽  
Wei Qi ◽  
Yan Jie Mao ◽  
Yin Hu ◽  
Xin Qing ◽  
...  

In the present work, expanded graphite (EG) was prepared by microwave irradiation. Then, the expanded graphite/polyaniline (EG/PANi) composite was synthesized in the typical method. The samples of EG and EG/PANi were characterized by SEM and IR analysis techniques. Adsorption property of EG/PANi composite for removing the dye, reactive brilliant red K-2BP, from aqueous solution was investigated. The effects of initial dye concentration and contact time, pH, sorbent dosage on the adsorption process were studied. Experimental data were modelled by Langmuir and Freundlich isotherms. Langmuir isotherm model fitted well the equilibrium data for EG/PANi composite comparing to the Freundlich isotherm model. The uptake capacity of EG/PANi for K-2BP was found to be 1.03047 mg/g. The results indicated that EG/PANi composite is not an ideal sorbent used for reactive dye removal.

2014 ◽  
Vol 2014 ◽  
pp. 1-5
Author(s):  
Song Xiuling ◽  
Du Huipu ◽  
Liu Shijun ◽  
Qian Hui

The adsorption of Ni(II) with D301R resin was investigated in this paper. The results showed that the saturated extent of adsorption Ni(II) by the resin was 84.3 mg/g. The equilibrium data of Ni(II) sorption was better described by Langmuir isotherm model (r2=0.994) while that of Ni(II) sorption also fitted in Freundlich isotherm model within the experimental concentration range. The amount of the constant (q0) of Ni(II) under 298 K in Langmuir model was 76.92 mg/g, which was close to the experimental results. The constant n was within 2–10 in Freundlich model; it was shown that adsorption of Ni(II) by the resin was easy to take place. The uptake kinetics followed the Lagergren pseudo-first-order rate equation (r2=0.9813). The particle diffusion controlled the adsorption process of Ni(II). The coefficient of the intraparticle diffusion increased with the increase of the pH values and the concentration of Ni(II) in aqueous solution. There was a drop of 20.1 cm−1for the bending vibration frequency of N–H bond. Results showed that the adsorption of Ni(II) by D301R anion exchange resin was the surface complexation through the infrared spectrum analysis.


2013 ◽  
Vol 394 ◽  
pp. 8-13
Author(s):  
Zong Qiang Zhu ◽  
Shuang Cao ◽  
Wen Hui Wei ◽  
Yi Nian Zhu

Static adsorption of Sb (III) on a porous biomorph-genetic composite of Fe2O3/Fe3O4/C (PBGC-Fe/C-B) was studied. The results showed that the kinetic curve of Sb (III) adsorption by PBGC-Fe/C-B had same change trend under initial concentration of 5, 10 and 50 mg/L. The fitting and regression analysis of four kinds of kinetic model indicated that, the adsorption kinetics of Sb (III) by the PBGC-Fe/C-B well follow the pseudo-second-order model (R2>0.9999). At different reaction temperature (25 °C, 35 °C and 45 °C), the adsorption capacity of Sb (III) by PBGC-Fe/C-B both increased with increasing the solution equilibrium concentration. While it showed a declined tendency with temperature increased. The Langmuir isotherm model (R2>0.98) and the Freundlich isotherm model (R2>0.95) had both better fitted with the equilibrium data.


2012 ◽  
Vol 18 (4-1) ◽  
pp. 497-508 ◽  
Author(s):  
Hussein Bahrami ◽  
Jaber Safdari ◽  
Ali Moosavian ◽  
Meisam Torab-Mostaedi

In this study, the adsorption of HF gas by three types of activated carbon has been investigated under vacuum condition. The effects of experimental parameters such as initial pressure of the HF gas, contact time and temperature on adsorption process have been investigated. The results showed that the adsorption of the HF gas onto activated carbon increased by increasing initial pressure of gas, while it decreased with increase in temperature. The Freundlich isotherm model fitted the equilibrium data better than the other isotherm models. Using Langmuir isotherm model, the maximum adsorption capacities of the first type, the second type and third type of activated carbon were 226.4, 268.8 and 258.9 mg/g, respectively. Experimental data were also evaluated in terms of kinetic characteristics of adsorption and it was found that the adsorption process followed well pseudo-second-order kinetics. Thermodynamic parameters, the change of free energy (?G?), enthalpy (?H?) and entropy (?S?) of adsorption were calculated at the temperature range of 28-55?C. The results showed that the adsorption of HF on activated carbon is feasible, spontaneous and exothermic.


2019 ◽  
Vol 2019 ◽  
pp. 1-11 ◽  
Author(s):  
Yong-gui Chen ◽  
Xue-min Liu ◽  
Hong-nan Lei ◽  
Wei-min Ye ◽  
Yu-jun Cui

To assess the potential use of laterite-bentonite mixture as waste landfill liner, a range of batch tests were conducted to study the influence of contact time, solid to solution ratio, pH, ion strength, and temperature on Pb(II) adsorption. The experimental results showed that the uptake of Pb(II) by laterite-bentonite mixture increases with the increase of contact time and the adsorption equilibrium can be reached within 30 minutes. This process can be delineated well using a pseudo-second-order kinetics equation. Besides, with the increase of solid to solution ratio (s/w) and pH, Pb(II) will be adsorbed more by the laterite-bentonite mixture. However, the uptake of Pb(II) will decrease when ion strength rises in the solution and this is due to the competitive adsorption and cation exchange between different cations. When conducting the batch test at 298 K and 323 K, respectively, the experiment results showed significant growth when temperature increases because the adsorption process is an endothermic reaction. This influence of temperate can be described better by the Langmuir isotherm model than that by the Freundlich isotherm model. In each experiment condition, the uptake of Pb(II) increases with the increasing of bentonite content, indicating a good improvement in the effect of bentonite on laterite used as landfill liner.


Author(s):  
Amal Benhathat ◽  
Moussa Amrani

In this paper, the synthesis and characterization of Ampelodesmos mauritanicus stems activated carbon (AMSAC) were studied. The produced activated carbon by phosphoric acid activation followed carbonisation was characterized by N2 adsorption-desorption isotherm, scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) analysis, and Fourier transform infrared (FTIR) spectroscopy. Sorption potential of AMSAC for the removal of methylene bleu from water was investigated. The experimental data found that AMSAC had high Brunauer-Emmett-Teller (BET) surface area of 1293 m2/g and abundant pores with specific volume of 1.23 m3/g. FTIR analysis reveals various functional groups on the surface of AMSAC which can be play an important role for the adsorption process. Langmuir isotherm model fitted well the equilibrium data for the methylene bleu comparing to the Freundlich isotherm model; the monolayer sorption capacity of AMSAC was found to be 411.8 mg/g at 25 °C


2009 ◽  
Vol 620-622 ◽  
pp. 555-558
Author(s):  
Yi Li ◽  
Xue Gang Luo ◽  
Zhao Liu ◽  
Yan Huang ◽  
Xiao Yan Long

The modified valonian tannin was prepared through sulfonated-mannich reaction and used to adsorb Cu (II) from the aqueous solutions. The adsorption capacity rapidly reached equilibrium within 2 hours. The effect of pH on adsorption was apparent, the amount of adsorption increased significantly as the pH increased from 2.0 to 4.0 and then leveled off at pH 4.0-6.0. Equilibrium data fitted well with Freundlich isotherm model compared to Langmuir isotherm model, indicating that adsorption takes place on heterogeneous surface of the modified valonia tannin. The adsorption capacity was increased by increasing initial concentrations. The maximum adsorption capacity of cooper ion was determined to be 56.200 mg/g at 100 mg/L concentration.


2012 ◽  
Vol 9 (4) ◽  
pp. 1823-1834 ◽  
Author(s):  
P. N. Palanisamy ◽  
A. Agalya ◽  
P. Sivakumar

Poly Pyrrle saw dust composite was prepared by reinforcement of natural wood saw dust (obtained fromEuphorbia Tirucalli Lwood) and Poly Pyrrole matrix phase. The present study investigates the adsorption behaviour of Poly Pyrrole Saw dust Composite towards reactive dye. The batch adsorption studies were carried out by varying solution pH, initial dye concentration, contact time and temperature. The kinetic study showed that adsorption of Reactive Red by PPC was best represented by pseudo-second order kinetics with ion exchange adsorption. The equilibrium data were analyzed by Freundlich and Langmuir isotherm model. The equilibrium isotherm data were fitted well with Langmuir isotherm model. The maximum monolayer adsorption capacities calculated by Langmuir model were 204.08 mg/g for Reactive Red at 303 K. The thermodynamic parameters suggest the spontaneous, endothermic nature of ion exchange adsorption with weak Vader walls force of attraction. Activation energy for the adsorption of Reactive by Poly Pyrrole Composite was 11.6387 kJ/mole, Isosteric Heat of adsorption was 48.5454 kJ/mole also supported the ion exchange adsorption process in which forces of attraction between dye molecules and PPC is weak.


2018 ◽  
Vol 15 (1) ◽  
pp. 6062-6069
Author(s):  
Keon Sang Ryoo

In this study, Chironomus yoshimatsui larvae were applied to remove Ni(II) and Cr(III) ions from wastewater. The sorption studies were carried out using laboratory-reared C. y. larvae. It was found that C. y. larvae are very susceptible to Cr(III) as compared to Ni(II). The survival capacity of C. y. larvae was sharply reduced when exposed to even low Cr(III) concentration. Sorption isotherm and kinetics of C. y. larvae for Ni(II) were determined by means of controlled experiments in a batch system. It was observed that sorpyion efficiency of Ni(II) was largely concentration dependent and more effective at lower concentration. At each equilibrium, Ni(II) was removed up to roughly 44∼80 %. Sorption data were better fitted to the Langmuir isotherm model because of its correlation coefficient R2 value greater than that of the Freundlich isotherm model. The sorption kinetics by C. y. larvae for Ni(II) was well described a pseudo-first-order rate expression. C. y. larvae have enormous potential for application in wastewater treatment technologies because they are widespread and abundant all around the world and can be easily kept in culture.


2018 ◽  
Vol 16 (3) ◽  
pp. 338 ◽  
Author(s):  
Bambang Rusdiarso ◽  
Rahmat Basuki ◽  
Sri Juari Santosa

Extraction and purification of humic acid from dry horse dung powder (HD-HA) was performed successfully and the purified HD-HA was then applied as sorbent to adsorb Zn2+. Extraction and purification were performed based on procedure of Stevenson (1994) under atmospheric air. Parameters investigated in this work consist of effect of medium sorption acidity, sorption rate (ka) and desorption rate constant (kd), Langmuir (monolayer) and Freundlich (multilayer) sorption capacities, and energy (E) of sorption. The ka and kd were determined according to the kinetic model of second order sorption reaching equilibrium, monolayer sorption capacity (b) and energy (E) were determined according to Langmuir isotherm model, and multilayer sorption capacity (B) was determined based on Freundlich isotherm model. Sorption of Zn2+ on purified HD-HA was maximum at pH 5.0. The novel kinetic expression resulted from proposed kinetic model has been shown to be more applicable than the commonly known Lagergren equation obtained from the pseudo-first order sorption model. The application of the equation revealed that the intercept of Lagergren equation, ln qe was more complex function of initial concentration of Zn2+ (a), Langmuir sorption capacity (b), and sorbed Zn2+ at equilibrium (xe).


2012 ◽  
Vol 27 ◽  
pp. 107-114
Author(s):  
Jagjit Kour ◽  
P. L. Homagai ◽  
M. R. Pokherel ◽  
K. N. Ghimire

The industrial discharge of heavy metals into waters' course is one of the major pollution problems affecting water quality. Therefore, they must be removed prior to their discharge into waste streams. An efficient and low-cost bioadsorbent has been investigated from Desmostachya bipinnata (Kush) by charring with concentrated sulphuric acid and functionalized with dimethylamine.It was characterised by SEM, FTIR and elemental analysis. The effect of pH, initial concentration and contact time of the metal solution was monitered by batch method. The maximum adsorption capacities were determined for Cd and Zn at their optimum pH 6. The equilibrium data were analysed using Langmuir and Freundlich isotherm models. Langmuir isotherm model fitted well and the rate of adsorption followed the pseudo second order kinetic equation.DOI: http://dx.doi.org/10.3126/jncs.v27i1.6669 J. Nepal Chem. Soc., Vol. 27, 2011 107-114  


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